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Posted to dev@cloudstack.apache.org by Wei ZHOU <us...@gmail.com> on 2013/05/30 17:47:00 UTC
[MERGE] diso_io_stat branch into MASTER
Hi,
I would like to merge disk_io_stat branch into master.
If nobody object, I will merge into master in 48 hours.
The feature includes
(1) Add disk I/O polling for instances to CloudStack.
(2) Add it to the instance vm disk statistics table.
(3) and add it to the usage database for optional billing in public clouds.
JIRA ticket: https://issues.apache.org/jira/browse/CLOUDSTACK-1192
FS (I will update later) :
https://cwiki.apache.org/confluence/display/CLOUDSTACK/Disk+IO+statistics+for+instances
Merge check list :-
* Did you check the branch's RAT execution success?
Yes
* Are there new dependencies introduced?
No
* What automated testing (unit and integration) is included in the new
feature?
Unit tests (UsageManagerTest) are added.
* What testing has been done to check for potential regressions?
(1) CloudStack UI display the bytes rate and IO rate.
(2) VM operations, including
deploy, stop, start, reboot, destroy, expunge. migrate, restore
(3) Volume operations, including
Attach, Detach
* Existing issue
(1)For XenServer/XCP, xepapi returns bytes per seconds instead of total I/O.
To review the code, you can try
git diff 7fb6eaa0ca5f0f58b23ab6af812db6366743717a
c30057635d04a2396f84c588127d7ebe42e503a7
Best regards,
Wei
[1]
https://cwiki.apache.org/confluence/display/CLOUDSTACK/Disk+IO+statistics+for+instances
[2] refs/heads/disk_io_stat
[3] https://issues.apache.org/jira/browse/CLOUDSTACK-1192<https://issues.apache.org/jira/browse/CLOUDSTACK-2071>(CLOUDSTACK-
*1192* - Add disk I/O statistics of instances)
Re: [MERGE] diso_io_stat branch into MASTER
Posted by Wei ZHOU <us...@gmail.com>.
Hi Wido,
I put all the database changes into setup/db/db/schema-410to420.sql.
I have tested on devcloud and our testing enviroment, it is ok.
-Wei
2013/5/31 Wido den Hollander <wi...@widodh.nl>
> Hi Wei,
>
>
> On 05/30/2013 05:47 PM, Wei ZHOU wrote:
>
>> Hi,
>>
>> I would like to merge disk_io_stat branch into master.
>> If nobody object, I will merge into master in 48 hours.
>>
>>
> I tried reviewing the whole patch and I mainly focused on the KVM side
> since that's what I know most about.
>
> Code wise it seems good, although I'm not sure about the .sql file.
>
> Shouldn't there be a creation of the tables in create-schema.sql as well?
> This is for newly created clusters.
>
> Wido
>
> The feature includes
>>
>> (1) Add disk I/O polling for instances to CloudStack.
>>
>> (2) Add it to the instance vm disk statistics table.
>>
>> (3) and add it to the usage database for optional billing in public
>> clouds.
>>
>> JIRA ticket: https://issues.apache.org/**jira/browse/CLOUDSTACK-1192<https://issues.apache.org/jira/browse/CLOUDSTACK-1192>
>> FS (I will update later) :
>> https://cwiki.apache.org/**confluence/display/CLOUDSTACK/**
>> Disk+IO+statistics+for+**instances<https://cwiki.apache.org/confluence/display/CLOUDSTACK/Disk+IO+statistics+for+instances>
>>
>> Merge check list :-
>>
>> * Did you check the branch's RAT execution success?
>> Yes
>>
>> * Are there new dependencies introduced?
>> No
>>
>> * What automated testing (unit and integration) is included in the new
>> feature?
>> Unit tests (UsageManagerTest) are added.
>>
>> * What testing has been done to check for potential regressions?
>> (1) CloudStack UI display the bytes rate and IO rate.
>>
>> (2) VM operations, including
>>
>> deploy, stop, start, reboot, destroy, expunge. migrate, restore
>>
>> (3) Volume operations, including
>>
>> Attach, Detach
>>
>> * Existing issue
>>
>> (1)For XenServer/XCP, xepapi returns bytes per seconds instead of total
>> I/O.
>>
>>
>> To review the code, you can try
>>
>> git diff 7fb6eaa0ca5f0f58b23ab6af812db6**366743717a
>> c30057635d04a2396f84c588127d7e**be42e503a7
>>
>> Best regards,
>>
>> Wei
>>
>> [1]
>> https://cwiki.apache.org/**confluence/display/CLOUDSTACK/**
>> Disk+IO+statistics+for+**instances<https://cwiki.apache.org/confluence/display/CLOUDSTACK/Disk+IO+statistics+for+instances>
>> [2] refs/heads/disk_io_stat
>> [3] https://issues.apache.org/**jira/browse/CLOUDSTACK-1192<https://issues.apache.org/jira/browse/CLOUDSTACK-1192>
>> <ht**tps://issues.apache.org/jira/**browse/CLOUDSTACK-2071<https://issues.apache.org/jira/browse/CLOUDSTACK-2071>
>> >(**CLOUDSTACK-
>> *1192* - Add disk I/O statistics of instances)
>>
>>
>
Re: [MERGE] diso_io_stat branch into MASTER
Posted by Prasanna Santhanam <ts...@apache.org>.
On Fri, May 31, 2013 at 02:16:31PM +0200, Wido den Hollander wrote:
>
> Shouldn't there be a creation of the tables in create-schema.sql as
> well? This is for newly created clusters.
>
Think Wei is right on this one - we froze create-schema.sql at 4.0
See: https://cwiki.apache.org/CLOUDSTACK/database-creator.html
--
Prasanna.,
------------------------
Powered by BigRock.com
Re: [MERGE] diso_io_stat branch into MASTER
Posted by Wido den Hollander <wi...@widodh.nl>.
Hi Wei,
On 05/30/2013 05:47 PM, Wei ZHOU wrote:
> Hi,
>
> I would like to merge disk_io_stat branch into master.
> If nobody object, I will merge into master in 48 hours.
>
I tried reviewing the whole patch and I mainly focused on the KVM side
since that's what I know most about.
Code wise it seems good, although I'm not sure about the .sql file.
Shouldn't there be a creation of the tables in create-schema.sql as
well? This is for newly created clusters.
Wido
> The feature includes
>
> (1) Add disk I/O polling for instances to CloudStack.
>
> (2) Add it to the instance vm disk statistics table.
>
> (3) and add it to the usage database for optional billing in public clouds.
>
> JIRA ticket: https://issues.apache.org/jira/browse/CLOUDSTACK-1192
> FS (I will update later) :
> https://cwiki.apache.org/confluence/display/CLOUDSTACK/Disk+IO+statistics+for+instances
>
> Merge check list :-
>
> * Did you check the branch's RAT execution success?
> Yes
>
> * Are there new dependencies introduced?
> No
>
> * What automated testing (unit and integration) is included in the new
> feature?
> Unit tests (UsageManagerTest) are added.
>
> * What testing has been done to check for potential regressions?
> (1) CloudStack UI display the bytes rate and IO rate.
>
> (2) VM operations, including
>
> deploy, stop, start, reboot, destroy, expunge. migrate, restore
>
> (3) Volume operations, including
>
> Attach, Detach
>
> * Existing issue
>
> (1)For XenServer/XCP, xepapi returns bytes per seconds instead of total I/O.
>
>
> To review the code, you can try
>
> git diff 7fb6eaa0ca5f0f58b23ab6af812db6366743717a
> c30057635d04a2396f84c588127d7ebe42e503a7
>
> Best regards,
>
> Wei
>
> [1]
> https://cwiki.apache.org/confluence/display/CLOUDSTACK/Disk+IO+statistics+for+instances
> [2] refs/heads/disk_io_stat
> [3] https://issues.apache.org/jira/browse/CLOUDSTACK-1192<https://issues.apache.org/jira/browse/CLOUDSTACK-2071>(CLOUDSTACK-
> *1192* - Add disk I/O statistics of instances)
>
Re: [MERGE] diso_io_stat branch into MASTER
Posted by Wei ZHOU <us...@gmail.com>.
Hi Wido,
I checked the source code. For RBD network devices, it should work well.
In
com.cloud.hypervisor.kvm.resource.LibvirtComputingResource.createVbd(Connect,
VirtualMachineTO, String, LibvirtVMDef)
disk.defNetworkBasedDisk(physicalDisk.getPath().replace("rbd:", "")
so disk.getPath() returns the path like /mnt/pool_uuid/disk_path.
I just committed a patch to support RBD on disk_io_stat branch which is not
needed, I will revert it.
-Wei
Re: [MERGE] diso_io_stat branch into MASTER
Posted by Wei ZHOU <us...@gmail.com>.
Wido, thanks for you review.
QEMU/libvirt can get the bytes/iops for individual volume.
path(or uuid) is a connection between volume (in cloudstack database) and
volume (in QEMU).
However, the first volume in QEMU is ROOTDISK, second volune is DATADISK.
Maybe I can use this to get the value for RBD.
- Wei
2013/5/30 Wei ZHOU <us...@gmail.com>
> For now, This supports KVM only. There is an issue in Xen support as
> xenapi returns I/O rate (bytes per seconds) instead of total I/O.
>
> -Wei
>
>
> 2013/5/30 Wei ZHOU <us...@gmail.com>
>
>> Hi Wido,
>>
>> I have not tested on network block devices like Ceph, as I have no
>> testing environment.
>> I will change the source code and point out this does not support
>> network block devices.
>> It will support in the future.
>>
>>
>> -Wei
>>
>>
>> 2013/5/30 Wido den Hollander <wi...@widodh.nl>
>>
>>> On 05/30/2013 05:47 PM, Wei ZHOU wrote:
>>>
>>>> Hi,
>>>>
>>>> I would like to merge disk_io_stat branch into master.
>>>> If nobody object, I will merge into master in 48 hours.
>>>>
>>>>
>>> First of all, awesome work! I created the ticket but never came around
>>> implementing it.
>>>
>>> I took a quick look at the code and saw this in LibvirtComputingResource:
>>>
>>> for (DiskDef disk : disks) {
>>> DomainBlockStats blockStats = dm.blockStats(disk.**getDiskLabel());
>>> String path = disk.getDiskPath(); // for example, path =
>>> /mnt/pool_uuid/disk_path/
>>> String diskPath = null;
>>> if (path != null) {
>>> ..
>>> }
>>>
>>> This will break with disks like RBD block devices running on Ceph. Since
>>> this are virtual disks they don't have a "path" element.
>>>
>>> Their XML in libvirt:
>>>
>>> <disk type='network' device='disk'>
>>> <driver name='qemu' type='raw' cache='writeback'/>
>>> <source protocol='rbd' name='rbd/mydisk:rbd_cache=1'>
>>> <host name='monitor.domain.lan' port='6789'/>
>>> </source>
>>> <auth username='libvirt'>
>>> <secret type='ceph' uuid='<uuid>'/>
>>> </auth>
>>> <target dev='vda' bus='virtio'/>
>>> </disk>
>>>
>>> Qemu/libvirt however counts the IOps, so I'm not sure why you completely
>>> rely on the path element for that.
>>>
>>> Have you tested this with RBD?
>>>
>>> Wido
>>>
>>> The feature includes
>>>>
>>>> (1) Add disk I/O polling for instances to CloudStack.
>>>>
>>>> (2) Add it to the instance vm disk statistics table.
>>>>
>>>> (3) and add it to the usage database for optional billing in public
>>>> clouds.
>>>>
>>>> JIRA ticket: https://issues.apache.org/**jira/browse/CLOUDSTACK-1192<https://issues.apache.org/jira/browse/CLOUDSTACK-1192>
>>>> FS (I will update later) :
>>>> https://cwiki.apache.org/**confluence/display/CLOUDSTACK/**
>>>> Disk+IO+statistics+for+**instances<https://cwiki.apache.org/confluence/display/CLOUDSTACK/Disk+IO+statistics+for+instances>
>>>>
>>>> Merge check list :-
>>>>
>>>> * Did you check the branch's RAT execution success?
>>>> Yes
>>>>
>>>> * Are there new dependencies introduced?
>>>> No
>>>>
>>>> * What automated testing (unit and integration) is included in the new
>>>> feature?
>>>> Unit tests (UsageManagerTest) are added.
>>>>
>>>> * What testing has been done to check for potential regressions?
>>>> (1) CloudStack UI display the bytes rate and IO rate.
>>>>
>>>> (2) VM operations, including
>>>>
>>>> deploy, stop, start, reboot, destroy, expunge. migrate, restore
>>>>
>>>> (3) Volume operations, including
>>>>
>>>> Attach, Detach
>>>>
>>>> * Existing issue
>>>>
>>>> (1)For XenServer/XCP, xepapi returns bytes per seconds instead of total
>>>> I/O.
>>>>
>>>>
>>>> To review the code, you can try
>>>>
>>>> git diff 7fb6eaa0ca5f0f58b23ab6af812db6**366743717a
>>>> c30057635d04a2396f84c588127d7e**be42e503a7
>>>>
>>>> Best regards,
>>>>
>>>> Wei
>>>>
>>>> [1]
>>>> https://cwiki.apache.org/**confluence/display/CLOUDSTACK/**
>>>> Disk+IO+statistics+for+**instances<https://cwiki.apache.org/confluence/display/CLOUDSTACK/Disk+IO+statistics+for+instances>
>>>> [2] refs/heads/disk_io_stat
>>>> [3] https://issues.apache.org/**jira/browse/CLOUDSTACK-1192<https://issues.apache.org/jira/browse/CLOUDSTACK-1192>
>>>> <ht**tps://issues.apache.org/jira/**browse/CLOUDSTACK-2071<https://issues.apache.org/jira/browse/CLOUDSTACK-2071>
>>>> >(**CLOUDSTACK-
>>>> *1192* - Add disk I/O statistics of instances)
>>>>
>>>>
>>>
>>
>
Re: [MERGE] diso_io_stat branch into MASTER
Posted by Wei ZHOU <us...@gmail.com>.
For now, This supports KVM only. There is an issue in Xen support as xenapi
returns I/O rate (bytes per seconds) instead of total I/O.
-Wei
2013/5/30 Wei ZHOU <us...@gmail.com>
> Hi Wido,
>
> I have not tested on network block devices like Ceph, as I have no testing
> environment.
> I will change the source code and point out this does not support network
> block devices.
> It will support in the future.
>
>
> -Wei
>
>
> 2013/5/30 Wido den Hollander <wi...@widodh.nl>
>
>> On 05/30/2013 05:47 PM, Wei ZHOU wrote:
>>
>>> Hi,
>>>
>>> I would like to merge disk_io_stat branch into master.
>>> If nobody object, I will merge into master in 48 hours.
>>>
>>>
>> First of all, awesome work! I created the ticket but never came around
>> implementing it.
>>
>> I took a quick look at the code and saw this in LibvirtComputingResource:
>>
>> for (DiskDef disk : disks) {
>> DomainBlockStats blockStats = dm.blockStats(disk.**getDiskLabel());
>> String path = disk.getDiskPath(); // for example, path =
>> /mnt/pool_uuid/disk_path/
>> String diskPath = null;
>> if (path != null) {
>> ..
>> }
>>
>> This will break with disks like RBD block devices running on Ceph. Since
>> this are virtual disks they don't have a "path" element.
>>
>> Their XML in libvirt:
>>
>> <disk type='network' device='disk'>
>> <driver name='qemu' type='raw' cache='writeback'/>
>> <source protocol='rbd' name='rbd/mydisk:rbd_cache=1'>
>> <host name='monitor.domain.lan' port='6789'/>
>> </source>
>> <auth username='libvirt'>
>> <secret type='ceph' uuid='<uuid>'/>
>> </auth>
>> <target dev='vda' bus='virtio'/>
>> </disk>
>>
>> Qemu/libvirt however counts the IOps, so I'm not sure why you completely
>> rely on the path element for that.
>>
>> Have you tested this with RBD?
>>
>> Wido
>>
>> The feature includes
>>>
>>> (1) Add disk I/O polling for instances to CloudStack.
>>>
>>> (2) Add it to the instance vm disk statistics table.
>>>
>>> (3) and add it to the usage database for optional billing in public
>>> clouds.
>>>
>>> JIRA ticket: https://issues.apache.org/**jira/browse/CLOUDSTACK-1192<https://issues.apache.org/jira/browse/CLOUDSTACK-1192>
>>> FS (I will update later) :
>>> https://cwiki.apache.org/**confluence/display/CLOUDSTACK/**
>>> Disk+IO+statistics+for+**instances<https://cwiki.apache.org/confluence/display/CLOUDSTACK/Disk+IO+statistics+for+instances>
>>>
>>> Merge check list :-
>>>
>>> * Did you check the branch's RAT execution success?
>>> Yes
>>>
>>> * Are there new dependencies introduced?
>>> No
>>>
>>> * What automated testing (unit and integration) is included in the new
>>> feature?
>>> Unit tests (UsageManagerTest) are added.
>>>
>>> * What testing has been done to check for potential regressions?
>>> (1) CloudStack UI display the bytes rate and IO rate.
>>>
>>> (2) VM operations, including
>>>
>>> deploy, stop, start, reboot, destroy, expunge. migrate, restore
>>>
>>> (3) Volume operations, including
>>>
>>> Attach, Detach
>>>
>>> * Existing issue
>>>
>>> (1)For XenServer/XCP, xepapi returns bytes per seconds instead of total
>>> I/O.
>>>
>>>
>>> To review the code, you can try
>>>
>>> git diff 7fb6eaa0ca5f0f58b23ab6af812db6**366743717a
>>> c30057635d04a2396f84c588127d7e**be42e503a7
>>>
>>> Best regards,
>>>
>>> Wei
>>>
>>> [1]
>>> https://cwiki.apache.org/**confluence/display/CLOUDSTACK/**
>>> Disk+IO+statistics+for+**instances<https://cwiki.apache.org/confluence/display/CLOUDSTACK/Disk+IO+statistics+for+instances>
>>> [2] refs/heads/disk_io_stat
>>> [3] https://issues.apache.org/**jira/browse/CLOUDSTACK-1192<https://issues.apache.org/jira/browse/CLOUDSTACK-1192>
>>> <ht**tps://issues.apache.org/jira/**browse/CLOUDSTACK-2071<https://issues.apache.org/jira/browse/CLOUDSTACK-2071>
>>> >(**CLOUDSTACK-
>>> *1192* - Add disk I/O statistics of instances)
>>>
>>>
>>
>
Re: [MERGE] diso_io_stat branch into MASTER
Posted by Wei ZHOU <us...@gmail.com>.
Hi Wido,
I have not tested on network block devices like Ceph, as I have no testing
environment.
I will change the source code and point out this does not support network
block devices.
It will support in the future.
-Wei
2013/5/30 Wido den Hollander <wi...@widodh.nl>
> On 05/30/2013 05:47 PM, Wei ZHOU wrote:
>
>> Hi,
>>
>> I would like to merge disk_io_stat branch into master.
>> If nobody object, I will merge into master in 48 hours.
>>
>>
> First of all, awesome work! I created the ticket but never came around
> implementing it.
>
> I took a quick look at the code and saw this in LibvirtComputingResource:
>
> for (DiskDef disk : disks) {
> DomainBlockStats blockStats = dm.blockStats(disk.**getDiskLabel());
> String path = disk.getDiskPath(); // for example, path =
> /mnt/pool_uuid/disk_path/
> String diskPath = null;
> if (path != null) {
> ..
> }
>
> This will break with disks like RBD block devices running on Ceph. Since
> this are virtual disks they don't have a "path" element.
>
> Their XML in libvirt:
>
> <disk type='network' device='disk'>
> <driver name='qemu' type='raw' cache='writeback'/>
> <source protocol='rbd' name='rbd/mydisk:rbd_cache=1'>
> <host name='monitor.domain.lan' port='6789'/>
> </source>
> <auth username='libvirt'>
> <secret type='ceph' uuid='<uuid>'/>
> </auth>
> <target dev='vda' bus='virtio'/>
> </disk>
>
> Qemu/libvirt however counts the IOps, so I'm not sure why you completely
> rely on the path element for that.
>
> Have you tested this with RBD?
>
> Wido
>
> The feature includes
>>
>> (1) Add disk I/O polling for instances to CloudStack.
>>
>> (2) Add it to the instance vm disk statistics table.
>>
>> (3) and add it to the usage database for optional billing in public
>> clouds.
>>
>> JIRA ticket: https://issues.apache.org/**jira/browse/CLOUDSTACK-1192<https://issues.apache.org/jira/browse/CLOUDSTACK-1192>
>> FS (I will update later) :
>> https://cwiki.apache.org/**confluence/display/CLOUDSTACK/**
>> Disk+IO+statistics+for+**instances<https://cwiki.apache.org/confluence/display/CLOUDSTACK/Disk+IO+statistics+for+instances>
>>
>> Merge check list :-
>>
>> * Did you check the branch's RAT execution success?
>> Yes
>>
>> * Are there new dependencies introduced?
>> No
>>
>> * What automated testing (unit and integration) is included in the new
>> feature?
>> Unit tests (UsageManagerTest) are added.
>>
>> * What testing has been done to check for potential regressions?
>> (1) CloudStack UI display the bytes rate and IO rate.
>>
>> (2) VM operations, including
>>
>> deploy, stop, start, reboot, destroy, expunge. migrate, restore
>>
>> (3) Volume operations, including
>>
>> Attach, Detach
>>
>> * Existing issue
>>
>> (1)For XenServer/XCP, xepapi returns bytes per seconds instead of total
>> I/O.
>>
>>
>> To review the code, you can try
>>
>> git diff 7fb6eaa0ca5f0f58b23ab6af812db6**366743717a
>> c30057635d04a2396f84c588127d7e**be42e503a7
>>
>> Best regards,
>>
>> Wei
>>
>> [1]
>> https://cwiki.apache.org/**confluence/display/CLOUDSTACK/**
>> Disk+IO+statistics+for+**instances<https://cwiki.apache.org/confluence/display/CLOUDSTACK/Disk+IO+statistics+for+instances>
>> [2] refs/heads/disk_io_stat
>> [3] https://issues.apache.org/**jira/browse/CLOUDSTACK-1192<https://issues.apache.org/jira/browse/CLOUDSTACK-1192>
>> <ht**tps://issues.apache.org/jira/**browse/CLOUDSTACK-2071<https://issues.apache.org/jira/browse/CLOUDSTACK-2071>
>> >(**CLOUDSTACK-
>> *1192* - Add disk I/O statistics of instances)
>>
>>
>
Re: [MERGE] diso_io_stat branch into MASTER
Posted by Wido den Hollander <wi...@widodh.nl>.
On 05/30/2013 05:47 PM, Wei ZHOU wrote:
> Hi,
>
> I would like to merge disk_io_stat branch into master.
> If nobody object, I will merge into master in 48 hours.
>
First of all, awesome work! I created the ticket but never came around
implementing it.
I took a quick look at the code and saw this in LibvirtComputingResource:
for (DiskDef disk : disks) {
DomainBlockStats blockStats = dm.blockStats(disk.getDiskLabel());
String path = disk.getDiskPath(); // for example, path =
/mnt/pool_uuid/disk_path/
String diskPath = null;
if (path != null) {
..
}
This will break with disks like RBD block devices running on Ceph. Since
this are virtual disks they don't have a "path" element.
Their XML in libvirt:
<disk type='network' device='disk'>
<driver name='qemu' type='raw' cache='writeback'/>
<source protocol='rbd' name='rbd/mydisk:rbd_cache=1'>
<host name='monitor.domain.lan' port='6789'/>
</source>
<auth username='libvirt'>
<secret type='ceph' uuid='<uuid>'/>
</auth>
<target dev='vda' bus='virtio'/>
</disk>
Qemu/libvirt however counts the IOps, so I'm not sure why you completely
rely on the path element for that.
Have you tested this with RBD?
Wido
> The feature includes
>
> (1) Add disk I/O polling for instances to CloudStack.
>
> (2) Add it to the instance vm disk statistics table.
>
> (3) and add it to the usage database for optional billing in public clouds.
>
> JIRA ticket: https://issues.apache.org/jira/browse/CLOUDSTACK-1192
> FS (I will update later) :
> https://cwiki.apache.org/confluence/display/CLOUDSTACK/Disk+IO+statistics+for+instances
>
> Merge check list :-
>
> * Did you check the branch's RAT execution success?
> Yes
>
> * Are there new dependencies introduced?
> No
>
> * What automated testing (unit and integration) is included in the new
> feature?
> Unit tests (UsageManagerTest) are added.
>
> * What testing has been done to check for potential regressions?
> (1) CloudStack UI display the bytes rate and IO rate.
>
> (2) VM operations, including
>
> deploy, stop, start, reboot, destroy, expunge. migrate, restore
>
> (3) Volume operations, including
>
> Attach, Detach
>
> * Existing issue
>
> (1)For XenServer/XCP, xepapi returns bytes per seconds instead of total I/O.
>
>
> To review the code, you can try
>
> git diff 7fb6eaa0ca5f0f58b23ab6af812db6366743717a
> c30057635d04a2396f84c588127d7ebe42e503a7
>
> Best regards,
>
> Wei
>
> [1]
> https://cwiki.apache.org/confluence/display/CLOUDSTACK/Disk+IO+statistics+for+instances
> [2] refs/heads/disk_io_stat
> [3] https://issues.apache.org/jira/browse/CLOUDSTACK-1192<https://issues.apache.org/jira/browse/CLOUDSTACK-2071>(CLOUDSTACK-
> *1192* - Add disk I/O statistics of instances)
>